Writing instrument



FIG. 1 is a perspective view of a first form of a writing instrumentshowing my new design;

FIG. 2 is an enlarged bottom plan view;

FIG. 3 is an enlarged top plan view;

FIG. 4 is a perspective view of a second form of the writing instrumentshowing my new design;

FIG. 5 is an enlarged bottom plan view of the FIG. 4 embodiment; and

FIG. 6 is an enlarged top plan view of the FIG. 4 embodiment._

The ornamental design for a writing instrument, as shown and described.